package com.zbangmall.util.common;

import java.io.*;

/**
 * 流相关的操作方法封装
 */
public final class StreamUtil {
	/**
	 * Read an input stream into a string
	 */
	public final static String streamToString(InputStream in) throws IOException {
		StringBuffer out = new StringBuffer();
		byte[]       b   = new byte[4096];
		for (int n; (n = in.read(b)) != -1; ) {
			out.append(new String(b, 0, n));
		}
		return out.toString();
	}

	/**
	 * Read an input stream into a byte[]
	 */
	public final static byte[] stream2Byte(InputStream is) throws IOException {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		int                   len  = 0;
		byte[]                b    = new byte[1024];
		while ((len = is.read(b, 0, b.length)) != -1) {
			baos.write(b, 0, len);
		}
		byte[] buffer = baos.toByteArray();
		return buffer;
	}

	/**
	 * @方法功能 InputStream 转为 byte
	 */
	public final static byte[] inputStream2Byte(InputStream inStream) throws Exception {
		int count = 0;
		while (count == 0) {
			count = inStream.available();
		}
		byte[] b = new byte[count];
		inStream.read(b);
		return b;
	}

	/**
	 * @return InputStream
	 * @throws Exception
	 * @方法功能 byte 转为 InputStream
	 */
	public final static InputStream byte2InputStream(byte[] b) throws Exception {
		InputStream is = new ByteArrayInputStream(b);
		return is;
	}

	/**
	 * 将流另存为文件
	 */
	public final static void streamSaveAsFile(InputStream is, File outfile) {
		try (FileOutputStream fos = new FileOutputStream(outfile)) {
			byte[] buffer = new byte[1024];
			int    len;
			while ((len = is.read(buffer)) > 0) {
				fos.write(buffer, 0, len);
			}

		} catch (IOException e) {
			e.printStackTrace();
			throw new RuntimeException(e);
		}
	}


}
